摘要:
Novel liquid crystal ester compounds exhibiting a low or negative dielectric anisotropy have a structural formula: ##STR1## where R.sub.1 is an alkyl group, R.sub.2 is an alkyl or alkoxy group, ##STR2## is a 1,4-disubstituted bicyclo(2,2,2) octane ring and ##STR3## is a 1,4-disubstituted ring selected from the following: (i) a 1,4-disubstituted bicyclo(2,2,2) octane ring;(ii) a trans-1,4-disubstituted cyclohexane ring;(iii) a laterally substituted benzene ring ##STR4## where of the two groups Y and Z one is a halogen or a cyano group and the other is hydrogen or a halogen or a cyano group such that Y is the same as Z.These esters may be used in a number of known applications including liquid crystal materials for multiplexed twisted nematic devices.The esters may be made by preparative methods involving known steps.
摘要:
Novel liquid crystal compounds exhibiting a low dielectric anisotropy have a structural formula: ##STR1## where R.sub.1 is an alkyl group, R.sub.2 is a group containing an alkyl group R and is either an alkyl group R, an alkoxy group OR, an alkylcarbonyloxy group OCOR or an alkoxycarbonyloxy group OCOOR, R.sub.1 and R containing up to 18 carbon atoms, ##STR2## is a trans-1,4-disubstituted cyclohexane ring ##STR3## or a 1,4-disubstituted bicyclo(2,2,2)octane ring ##STR4## and Ar is a 1,4 disubstituted benzene ring ##STR5## a 3-fluoro-1,4 disubstituted benzene ring ##STR6## or a 2,6 disubstituted naphthalene ring ##STR7## These compounds may be used in liquid crystal mixture compositions for use in a number of known electro-optic effects.The compounds may be prepared by routes in which the individual steps involved are known.
摘要:
A novel liquid crystal compound has the molecular structure: ##STR1## where R is an alkyl group, which may contain up to 18 carbon atoms and which may be normal or branched and may contain a chiral center, ##STR2## is a bicyclo (2.2.2) octane ring, --X-- is and Y is a cyano group CN or R.sup.1 or OR.sup.1 where R.sup.1 has the same definition as R.The compound may be used in mixtures with other liquid crystal compounds in the same or other families and the compound or mixtures may be used in known liquid crystal devices, eg the twisted nematic and cholesteric-to-nematic phase change devices, depending on its properties.
摘要:
Anisotropic compounds having negative DC anisotropy and improved photochemical stability have the formula (1) given in patent claim 1; none of the benzene rings present in the molecule (1) is bonded directly to two oxygen atoms, as a result of which quinoidal bonding states which reduce the photochemical stability of anisotropic compounds in the case of benzene rings with two lateral nitrile groups are excluded.
摘要:
Nematic compounds with a negative DC antisotropy, characterized by the formula I ##STR1## in which m=1 or 2, r is zero or 1 and m+r=1 or 2, and R.sup.1 and R.sup.2 are identical or different and are selected from alkyl and alkoxy groups each having 1-12 carbon atoms in a straight or branched chain, which may be chiral, Z is a bridge member selected from a single bond and the groups of the formulae --CH.sub.2 CH.sub.2 --, --OCH.sub.2 --, --O--CO-- or --CO--O--, one of the groups X and Y is selected from fluorine, chlorine, bromine and cyano and the other of the groups X and Y is selected from hydrogen, fluorine, chlorine, bromine and cyano, with the proviso that m=r=1 if X and Y are both cyano, are suitable as components for liquid crystal mixtures having an overall negative DC anisotropy, such as are required in particular for electro-optical displays of the type of guest/host displays or homotropic-nematic displays.
摘要翻译:具有负直流消偏性的向列化合物,其特征在于其中m = 1或2,r为0或1,m + r = 1或2,并且R 1和R 2相同或不同并且被选择的式I 在直链或支链上各自具有1-12个碳原子的烷基和烷氧基,其可以是手性的,Z是选自单键的桥连体,式-CH 2 CH 2 - , - OCH 2 - ,-O -CO-或-CO-O-,基团X和Y之一选自氟,氯,溴和氰基,X和Y中的另一个选自氢,氟,氯,溴和氰基,与 条件是如果X和Y都是氰基,则m = r = 1,适合作为具有总的负DC各向异性的液晶混合物的组分,例如特别对客体/主机显示器类型的电光显示器 或同向向列型显示器。
摘要:
Anisotropic compounds of the formula (1) specified in claim 1 are suitable, owing to their low .DELTA..epsilon./.epsilon..perp. values for liquid crystal displays which have high information densities of for examples up to 10.sup.6 image dots and accordingly need to be highly multiplexible; compared with known compounds they offer improved application properties and are relatively simple to synthesize.
摘要:
A novel liquid crystal compound has the molecular structure: ##STR1## where R is an alkyl group, which may contain up to 18 carbon atoms and which may be normal or branched and may contain a chiral center, ##STR2## is a bicyclo (2.2.2) octane ring, ##STR3## is a phenyl ring and CN is a cyano group, n being an integer greater than 0 preferably 1 or 2.The compound may be used in mixtures with other liquid crystal compounds in the same or other families and the compound or mixtures may be used in known liquid crystal devices, eg the twisted nematic and cholesteric-to-nematic phase change devices, depending on its properties.
摘要:
A method and system for applying a liner material to a contoured surface, such as an exposed rock face in an underground hard rock mine, is disclosed. Locations of a plurality of spatially distributed surface grid points on the contoured surface may be detected so as to generate a representative topographical profile of the contoured surface. Based on the plurality of surface grid points, a spray path for a liner application device configured to emit a spray of the liner material may be determined. In some cases, the spray path may have a trajectory that follows the topographical profile of the contoured surface offset therefrom within a spray range of the liner application device. Liner material may then be sprayed onto the contoured surface while controlling the liner application device to undertake at least one pass of the spray path.
摘要:
Anisotropic compounds of the formula (1) specified in claim 1 are suitable, owing to their low .DELTA..epsilon./.epsilon..perp. values for liquid crystal displays which have high information densities of for examples up to 10.sup.6 image dots and accordingly need to be highly multiplexible; compared with known compounds they offer improved application properties and are relatively simple to synthesize.